Evaluating the aperiodic component of neural power spectra as a marker of aging and neurodegeneration: A meta-analysis

The aperiodic component of the power spectrum has emerged as a crucial factor in understanding EEG and MEG signals, offering insights beyond traditional oscillatory analyses. Unlike rhythmic brain activity, the aperiodic component reflects non-periodic neural dynamics and follows a characteristic 1/f trend. It is quantified by two parameters: offset and exponent. Recent studies suggest it may serve as a potential biomarker for healthy aging and pathology, yet findings remain inconsistent across literature. This meta-analysis aims to address these discrepancies. The results indicate that both offset and exponent decline in older adults compared to younger adults. However, when assessing its potential as a clinical marker, no significant differences in offset and exponent were observed between patients and healthy controls. A subgroup analysis of neurodegenerative disorders also yielded no significant results, indicating that aperiodic activity does not reliably differentiate between pathological conditions. These findings highlight the aperiodic component as a promising marker of aging-related neural changes but challenge its utility as a clinical diagnostic tool. Future research should refine methodological approaches and explore its potential in tracking disease progression or treatment responses. Focusing on the aperiodic component for monitoring brain health could contribute to more personalized intervention strategies.